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Amethyst

UNB-2020-0019Minerals » Tectosilicates

Description

Amethyst [SiO2] occurring as a cluster of short, intergrown quartz crystals developed on a pale cream to grey matrix. Crystals are transparent to translucent and range from very pale lavender to medium purple, with uneven colour distribution and locally darker purple zones. Individual crystals display vitreous lustre and pointed terminations. Colourless to milky quartz is also present along portions of the specimen. This is a test.

Specifications

Object nameAmethyst
IDUNB-2020-0019
Legal statusPermanent collection
CategoryMineral
Classification
Mineral group:
Tectosilicates
Composition
  • CaB2Si2O8(OH,F)2
  • (Ca,Na2,K2)Al2Si4O12•6H2O
  • (Ca,Na)AlSi2O8
  • (Na2,K2)Al2Si4O12•2H2O
  • (Na,Ca)4(Al,Na)3Si9O24(Cl,CO3)2
  • (MAlO2)(SiO 2)x(H2O)y
  • (Na,K)AlSiO4
  • Na2Al2Si3O10·2H2O
  • KAlSi3O8
  • Na2Ca2Al6Si9O30·8H2O
  • K(AlSi2O6)
  • CaAl2Si4O12·4H2O
  • Pectolite NaCa2Si3O8(OH)2H2O with trace amounts of copper
  • (Ca,Na)(Al,Si)4O8
  • SiO2 with water inclusion
  • (Na,Ca)4-8Al6Si6(O,S)24(Cl,SO4)1-2
  • Na8(Al6Si6O24)Cl2
  • CaAl2Si3O10·3H2O
  • SiO2
  • (Cs,Na)2Al2Si4O12·2H2O
  • (Na, Ca)(Al, Si)AlSi2O8
  • KAlSi3O8
  • (Na,K)AlSi3O8
  • (Na,K)AlSi3O8
  • CaAl2Si2O8
  • SiO2
OriginUnknown
Pieces1
PartialNo
Measurements
  • 8cm x 4.5cm x 3cm

Map of Origin

Publications

  • Chesterman, C.W. 1979. Audubon Society, Field Guide to North American Rocks and Minerals. Knopf.